1. Field of the Invention
The present invention relates to a multi-band antenna and an electronic device provided with the same for communication purposes.
2. Description of the Related Art
A conventional electronic device is generally provided with a plurality of antennas corresponding respectively to different frequency bands. For example, a conventional electronic device may be provided with a dual-band inverted-F antenna covering frequency bands of 2.4˜2.5 GHz and 5.15˜5.875 GHz for Wireless Local Area Network (WLAN), and a single-band monopole antenna covering a frequency band of 3.3˜3.8 GHz for Worldwide Interoperability for Microwave Access (WiMAX). Moreover, for each type of the dual-band inverted-F antenna and the single-band monopole antenna, the conventional electronic device requires at least two antennas in order to achieve signal diversity.
However, with the rapid development of wireless communication, the dual-band inverted-F antenna has become obsolete. Instead, there is a requirement of a single unitary multi-band antenna capable of covering all of the above-mentioned frequency bands or even a broader frequency band (e.g., 2.3˜2.7 GHz).
Moreover, in order to achieve a better effect of the signal diversity, insertion loss between two multi-band antennas operating in a same frequency band should be smaller than −20 dB.